The contact owns a 2015 Ford F-150. The contact stated while driving 20 MPH and crossing an intersection, the accelerator was depressed and there was an abnormal sound coming from the transmission. The contact stated that the transmission unexpectedly shifted out of the intended gear into neutral(N). The Service Vehicle Soon warning light was illuminated. The vehicle was taken to an independent mechanic where the vehicle was diagnosed, and the contact was informed that the valve body plate was faulty and needed to be replaced. The vehicle was repaired. The manufacturer was notified of the failure. The approximate failure mileage was 80,000.